1. Field of the Invention
The present invention relates generally to children's participatory play devices, and, in particular, to an impact-safe projectile launcher for propelling foam or other projectiles using pressurized and/or high-velocity air.
2. Description of the Related Art
Over the past decade there has been a steady proliferation of commercial play structures designed to meet the recreational needs of young families. These play structures are typically adapted for either water play and/or non-water play use, as desired, and can provide a safe and exciting alternative to more traditional parks and playgrounds. Participatory play structures, that is, play structures that allow play participants to actively participate in creating desired effects, are particularly desirable because of their widely recognized entertainment and educational benefits.
The size and sophistication of modem participatory play structures has grown tremendously as the basic concepts of participatory play have been successfully expanded and adapted to a wide variety of fun and exciting play mediums and play themes. These play structures allow a great variety of stimulating and entertaining play activities for children and young adults. Such participatory play structures have found broad application to a variety of play media and participatory play activities incorporating a wide range of fun and exciting play effects, mechanisms, springs, cams, pulleys, gears, and the like, all of which are employed to provide a play experience which is both fun and, at the same time, educational. See, for example, my co-pending application U.S. Ser. No. 08/621,173, incorporated herein by reference.
One especially exciting and entertaining participatory play activity, particularly for play structures utilizing water as the primary play medium, involves shooting a stream of water at selected targets and/or other play participants. This usually entails some form of a water cannon, water gun, squirt gun, spray hose or the like, which play participants can operate to surprise other play participants or to achieve desired effects. Such participatory play activities provide particular benefits in developing children's motor skills and hand-eye coordination. It also provides endless fun for play participants, who enjoy the challenge of trying to hit various targets and/or one another.
It would be desirable to replicate this play activity for participatory play structures utilizing dry play mediums, such as foam balls or the like. However, unlike a stream of water, which assumes a relatively streamlined aerodynamic shape during flight and which disperses harmlessly on impact, dry participatory play media typically involves the use of discrete articles having a defined size, shape and mass, which remain constant during flight and upon impact. Moreover, while water is easily regulated at the source to ensure that the pressure and impact velocity of the resulting stream remains within predetermined safe parameters, the impact velocity of discrete projectiles is not so easily regulated. Thus, while it is possible to project an impactsafe stream of water over relatively large distances of 20 to 30 feet with fairly good accuracy, the same task becomes considerably more difficult when using discrete projectiles such as foam balls.
Various guns or projectile launchers have been proposed over the years for the general purpose of launching projectiles. U.S. Pat. No. 5,343,849 to Steer, for example, describes a variety of air-powered guns heretofore available. These air-powered guns typically have barrels and gun bodies made of lightweight plastic and are designed to be portable for carrying around during simulated "war games." As disclosed, for example, in U.S. Pat. No. 5,113,842 to Moormann, such air guns typically utilize a plunger or bladder to pump or compress air within the gun stock in order to build sufficient pressure to discharge a projectile such as a ping-pong ball or soft foam ball. However, due to the relative small size of these air guns and their limited capacity for safely containing a charge of compressed air, the projectiles generally do not travel great distances and the guns are not particularly accurate. Most of these guns are inexpensive toys available from retail toy stores and, therefore, they are not intended to be particularly durable. They would not, for instance, be able to withstand repeated or long-term heavy use and abuse by multiple play participants playing on, in or around a participatory play structure.
Longer range, more accurate air guns are also known which fire pellets or BBs using a compressed source of CO.sub.2 or other compressed gas. These typically resemble handguns or rifles and are not intended for use by children without adult supervision or for use by small children. The BBs are usually steel or copper balls about 0.175" in diameter. Due to their small size and high velocity, BBs can be very painful and even dangerous if they impact a human target, especially at close range. Thus, these types of air guns are not at all well suited for use in a participatory play environment in which children and young adults may be exposed to possible danger.
Other types of ball or projectile launchers include baseball pitching machines and tennis ball throwing machines. These generally use a mechanical arm or a sleeve of compressed air to propel a series of balls in a predetermined or preset trajectory. The users are typically the recipients of the balls and do not directly control the delivery of the balls from the machine or their trajectory. Thus, these types of machines are primarily used for hitting practice in softball, baseball and/or tennis. They would not typically be used, for example, for propelling balls at targets or at other persons. Accordingly, such projectile launchers would not be suited for use in a participatory play environment where the balls could strike and possibly cause injury to play participants.